Compensating mechanical image stretch in a printing device

Abstract

The present invention compensates a printed image for distortions caused by mechanical image stretch. One embodiment comprises a memory configured to store compensation data, the compensation data corresponding to distortion in a printed image caused by mechanical image stretch, and a processor configured to generate a compensated image data by combining data corresponding to the image and the compensation data, and configured to communicate the compensated image data to a printing system.

1. A method for compensating images, the method comprising the steps of:
 receiving image data corresponding to a captured image;  
 sensing at least one characteristic of a sheet of paper transported by a printing system;  
 selecting one of a plurality of compensation data, the selected compensation data corresponding to a sensed characteristic;  
 receiving compensation data, the compensation data corresponding to distortion in a printed image caused by mechanical image stretch associated with at least one mechanical system;  
 combining the image data with the compensation data; and  
 generating compensated image data from the combined image data and the compensation data.  
 
     
     
       2. The method of  claim 1 , further comprising:
 communicating the compensated image data to a printing device; and  
 generating at least one compensated raster line by compensating at least one of the generated raster lines using the compensated image data so that distortion in the printed image caused by the mechanical image stretch is reduced.  
 
     
     
       3. The method of  claim 1 , further comprising determining image distortion caused by the mechanical system, wherein the mechanical system resides in a paper transport unit configured to transport a printing medium in proximity to a printing unit such that the compensated raster line is printed on the printing medium. 
     
     
       4. The method of  claim 1 , further comprising determining image distortion caused by the mechanical system, wherein the mechanical system resides in a printing unit configured to print a compensated raster line on a printing medium. 
     
     
       5. The method of  claim 1 , further comprising determining image distortion caused by the mechanical system, wherein the mechanical system resides in an image capture device configured to generate the received image data. 
     
     
       6. The method of  claim 1 , further comprising determining the compensation data from at least one design parameter of the mechanical system. 
     
     
       7. The method of  claim 1 , further comprising:
 printing a captured image of a reference image, the reference image having at least one reference point;  
 comparing a corresponding point on the printed captured image and the reference point on the reference image; and  
 determining the compensation data from a difference between a corresponding point on the printed captured image and the reference point on the reference image.  
 
     
     
       8. The method of  claim 7 , wherein the reference point on the reference image comprises at least one selected from a group consisting of a known distance, a known color, a known shape, a known pattern and a known scale. 
     
     
       9. The method of  claim 1 , wherein the step of generating the compensated image data includes the step of magnifying at least a selected portion of the received image data. 
     
     
       10. The method of  claim 1 , wherein the step of generating the compensated image data includes the step of reducing at least a selected portion of the received image data. 
     
     
       11. The method of  claim 1 , wherein the sensed characteristic comprises at least one selected from a group consisting of a paper type, a friction coefficient and a paper size. 
     
     
       12. A method for compensating images, the method comprising the steps of:
 receiving image data corresponding to a captured image;  
 receiving compensation data, the compensation data corresponding to distortion in a printed image caused by mechanical image stretch associated with at least one mechanical system;  
 combining the image data with the compensation data; and  
 generating compensated image data from the combined image data and the compensation data,  
 wherein receiving the compensation data and generating the compensated image data is performed for a plurality of printing systems, and wherein each printing system includes at least one unique mechanical system causing mechanical image stretch, such that the generated compensated image data is unique to each one of the plurality of printing systems.